Collocations for unfit - adj.

be, look
become
make sb/sth, render sb/sth
His conduct made him unfit to act as director of a company.

consider sb/sth, declare sb/sth, deem sb/sth, find sb/sth
The house was declared quite unfit for human habitation.

completely, quite, totally
medically, mentally, morally, physically

for
completely unfit for our purposes
She was found unfit for work.
The prison service was declared ‘unfit for purpose’. (BrE)

be, feel, look
become

very
completely, quite
slightly

Unfit is used with these nouns:
mother, parent